In order to replicate the issue just connect any external SSD wait for a while and it will be disconnected with message "Disk Not Ejected Properly". SSD is connected to M1 MacBook Pro. It's neither a cable issue because I tried multiple cables, nor an SSD issue as everything worked just fine before upgrade.
Do do do report it!
*Wish I'd reported it so as soon as the problem arose, insead of thinking it was everything but my MBP and losing a screen and 2 disks. Genius Bar was unable to replicate it, so the tech leaned towards the idea that it wasn't a Mac fault. The Mac was finally replaced, but it was a long battle that cost me dearly in time, data loss, stress and hardware.
As others have said, Apple will only take this seriously if they receive numerous reports about it.
It's also not a coincidence that so many people have described it happening on multiple drives – including me (4 external drives, different models, different ages). Like you I've done the dance with cables, removing hubs etc. I also have various other issues including problems with dictation, which Apple genius bar diagnosed as being due to intermittent (wired) Internet connection via Thunderbolt ports. I'm still having this problem although I have yet to upgrade to Sonoma. I don't know enough about the relationship between hardware/software/firmware but I can't help thinking there is something else at play because it is not just Sonoma.
It's not just SanDisk. I have the same problem with a 4TB Seagate SSD. I'm concerned that some files and folders are being corrupted by this, but it's difficult to tell when the problem occurs. It's rarely while I am activity working at my laptop and most often when I return after the screensaver has come on and maybe the Mac has put itself to sleep.
Complete wrong, its disconnects when Mac is awake and disconnect drive when copy process going. Also, this drives very well working before sonoma and very interesting it normally work on Linux and Win stations without any issues with sleep, power of bla bla bla etc.
Same problem with Sonoma 14.3.1 on a new (Nov 2023) MacBook Pro M3 Pro Silicon. Happened infrequently but many times with a 5T external HDD. Tried 3 different cables (USB Micro B to USB A into the USB A female to USB C adapter), happened on all 3 cables. Tried a different 5T HDD, happened with it also. This never happened with either of these same HDD on my old laptop (MacBook Pro mid-2014 with Mojave). Today It has happened a dozen times in one afternoon with a Lexar 128 GB USB flash "thumb" memory stick. I tried 2 different adapters, right and left rear USB-C ports on the laptop, happened multiple times in every configuration. Results suggest to me a bug in Sonoma. When it happens while copying to the Lexar, I get "device disappeared", then a separate alert "not ejected properly".
I initially thought the same about my SanDisk Portable Extreme and returned it, but had exactly the same issue with both the replacement and all my other drives (la Cie and OWC, Samsung... I also previously returned the Samsung thinking it was faulty and and replaced it with the first San Disk). I was on Monterey at the time and lost a lot of data due to corruption, and a fried disk. The problem was initially resolved by changing the Thunderbolt ports on the MBP. However, it returned a few months later, so the logic board was changed and o/s upgraded to Ventura. That didn't cure it either.
Most people seem convinced it's Sonoma, but not in my case. What mac do you have? In case yr using an Intel, it's recently been suggested to me it may be a known issue with the i9 processor.
Same issue MacBook Pro MP1 running Sonoma 14.2. I thought it was issue with my Samsung T7 Shield 4Gb SSD (which did die once and was replaced by Samsung), but the second unit had this issue over night when the computer would go into standby. Sent the second T7 back and Samsung reported nothing wrong with it. I noticed the same issue happening with a Seagate 5Gb HD. I've gone through settings to basically keep the computer nearly fully-on at all times and never let drives go to standby... still happens. For sure seems like a Sonoma issue.
To add, there is a Reddit thread on the same issue and an interesting comment claiming Apple is aware of the issue and is suggesting to wait for a fix. Which is probably good news.
seems that reports are private Victor is right
This disk is couple month old, and works fine with windows, so my assumption is that apple messed up in Sonoma somehow, maybe it is related to power management of the usb c ports
hi! I bought a new enclosure and new m.2 ssd this weekend. Tried getting it to work with my Sonoma machine, didn't work. Plugged it into my Monterey machine, zero problems. It's a Sonoma issue...
Same issue here. Last night upgraded to Sonoma. After the upgrade my external drive keeps disconnecting.
I can confirm that this is happing in Sonoma for me occasionally.
Same thing is happening for me after upgrading to Sonoma today. M2 Mac mini keeps randomly disconnecting my external Kingston SSD. Very annoying
Is it possibly Apple is writing code to steer customers from buying cheaper storage and avoiding the expensive options Apple offers, (most especially with the 2023 Apple M-2 MacMini?$$$) IMHO
EXACTLY, it's all about the money. They live from harware.
External SSD keeps disconnecting after upgrading to Sonoma
